Around 13.00 UTC the system was most active with the heaviest storms in its central part west-south-west of the Netherlands. A squall line formed along the surface trough. In the northern part of the line heavy thunderstorms were reported with hail and damaging gusts up to 70 kts.

The original Cold Front has amalgamated with the thermal trough which was originally situated in front of it. Significant is the sharp ridge in the isobars at the rear of the squall line due to the outflow of cold air from the storm cells. In the north-western part of the system the outflow patterns are to be seen over the North Sea. They may be the result of a strong rising Warm Conveyor Belt over the original Cold Front. Relative streams can give more clarity about this feature.

After 13.00 UTC the activity of the system decreased although thunderstorms were still reported in the remnants of the cluster at 18.00 UTC.